[morzh]

I think this is the reason A amps are used as low power drivers for sensitive speakers. Class A is rarely used in hi-fi where you need mor than 1-2W to drive some 105dB speaker which will be very loud even at this power level.
Pushpull can be used where hi-fi output is needed for larger power, lower sensitivity speakers, like today's compression types, whose power is easily over 100W but the sensitivity is just above 80dB which pretty much means that one needs 100W to produce the same pressure as the 100dB speaker would produce at 1W.

So what you have will shine with old style paper cone wide band speaker or a speaker system like any legacy Klipsch jorn-loaded type.